NEET Physics Nuclei Questions Solved


The electric potential between a proton and an electron is given by V=V0lnrr0 where r0 is a constant. Assuming Bohr’s model to be applicable, write variation of rn with n, n being the principal quantum number

(a) rnn            (b)  rn1/n
(c) rnn2           (d) rn1/n2

(a) Potential energy U=eV=eV0lnrr0 
 Force F=-dUdr=eV0r .
 The force will provide the necessary centripetal force. Hence mv2r=eV0rv=eV0m …..(i)
and mvr=nh2π               …..(ii)
From equation (i) and(ii) mr=nh2πmeV0  or r ∝ n

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